motor connections

[fireman22]

hi, inherited a faulty fan motor, i suspect capacitor but wires have been removed and put back but i cant be sure they are in correct order etc.
motor has six cables marked plus the earth U1, U2, Z1, Z2, TK and TK.
need drawing or advice anything really.

 

[mapj1]

This is not guaranteed, and should only be tried on the clear understanding it might not work. If it overheats and/or draws vast amounts of current if when you try this, its not as I describe.. Not all motor makers agree.
If you have a meter you can check, U1 to T1, is one winding U2 to T2 is the other. Hopefully no connection between the 2 windings.
1st winding connects across mains directly, 2nd goes across the mains in series with the cap. If in doubt put the lower resistance winding in series with the cap, and only change that if the torque is lacking. If it goes backwards swap over the ends of one of the coils (but not both. )

TK, no idea what it stands for, but the only thinks I would expect is either a thermal overload sensor or a switch which opens at a preset speed. check with meter for short circuit, and no change in that when you wrap a string around the shaft and pull to spin it fast... (keep fingers clear..)if still short circuit, its a temperature trip - wire in series with supply, like a fuse.

Beware of gyroscopic effects when firing it up if not firmly clamped.

 

[Big_Spark]

If it is a fan motor the two sets of windings could also be speed settings. Vent-Axia units often have multiple windings that give different speeds by connecting different numbers of poles.

The U1 and U2, as Map has pointed out are likely to be one winding and the Z1/Z2 will be the other.

TK is normally the installed Thermal Overload of the motor so again Map is correct in this assessment.

Speed 1 on VA units will be U1 and U2, Speed 2 Z1 and Z2 and speed three is usually acheived by linking U2 to Z1 with the supply connected to U1 and Z2.

Many of these units do not have caps installed, they may be remote from the motor, this is very common in units from Fan Coils, I have just such a motor sat here. Map is correct in his assessment of the need to connect a cap in series with the lowest resistance winding, but I would suggest that you determine that it needs one in the first place as some small Fan motors have permanent magnets in the rotor which means there is no need for a cap to be installed as the rotating magnetic field in the stator will drag the static magnetic field with it, thus turning the rotor and the fan. This type is only used in motors that have no real torque requirments, and Fans are usually of this type..

What is the power rating of the motor as this may give a clue to the type. Those containing permanent Mags are usually below 200W in power, normally about the 40 to 150W mark, so if this motor is larger than it is unlikely to be of this type.